Studies will be continued on the mechanism of action of coenzyme A transferase with particular reference to the role of substrate specificity in providing the driving force for catalysis and the examination of model reactions. Inhibition of this by thiols and hydroxamic acids will be investigated as will the conformation changes of the enzyme-CoA intermediate by use of the rate of tritium exchange. Studies will be continued on the general acid-catalyzed aminolysis of phenyl acetate and studies initiated on the general base catalyzed aminolysis of thiol esters. Viscosity and isotope effect studies will be carried out on transimination reactions.